Santen Files for Manufacturing and Marketing Approval for STN1011402 (Epinastine Hydrochloride) Ophthalmic Cream in Japan - Applied once daily to periocular area, new formulation for treatment of allergic conjunctivitis-

March 27, 2023, Osaka, Japan - Santen Pharmaceutical Co., Ltd. (hereinafter Santen) announced today that it has filed an application for manufacturing and marketing approval of STN1011402 (generic name: epinastine hydrochloride) ophthalmic cream in Japan.

This formulation is a treatment for allergic conjunctivitis containing 0.5% epinastine hydrochloride that is applied once daily to the periocular area (upper and lower eyelids). Histamine H1 receptor antagonist eye drops are widely used in the treatment of allergic conjunctivitis and need to be applied twice or four times a day. This formulation, which is applied once a day, eliminates the burden of daytime application for patients and since application involves direct contact with the area where the preparation is applied, this formulation is easy to handle even for patients who have difficulty using eye drops, such as pediatric and other patients who require assistance. It may provide a new dosage form option (ophthalmic cream) for the treatment of allergic conjunctivitis, which to date is typically treated with eye drops.

Epinastine hydrochloride, the active ingredient in this formulation, was discovered and developed by Boehringer Ingelheim in 1975. Its main action is selective histamine H1 receptor antagonism, and it also inhibits the release and production of chemical messengers from mast cells. Clinical studies conducted in Japan have confirmed the efficacy of this product in regards to suppressing itchy eyes and conjunctival hyperemia, the main symptoms of allergic conjunctivitis. No serious ocular or systemic adverse reactions have been observed.

Allergic conjunctivitis is a condition in which allergens (substances that cause allergic reactions) such as pollen adhere to the surface of the eye, causing inflammation of the conjunctiva. According to a 2017 prevalence survey conducted by the former Japanese Society of Ophthalmic Allergy Research (currently the Japanese Society of Ocular Allergology), the prevalence of allergic conjunctivitis in Japan was 48.7%1, and the rate has been increasing in recent years.

“There are several types of allergic conjunctivitis and in Japan, seasonal allergic conjunctivitis is particularly common during the period of high pollen counts, especially cedar pollen,” said Peter Sallstig, Chief Medical Officer at Santen. “Patients suffer from a decreased Quality of Life (QOL) due to conjunctivitis symptoms such as intense itching and redness of the eyes. This is the world’s first* drug for allergic conjunctivitis in a formulation that is applied to the periocular area (upper and lower eyelids), and we are very excited to pursue the possibility of innovative treatment options through this development.”

As a specialized company dedicated to eye health, Santen is committed to reducing the loss of social and economic opportunities for people around the world due to eye conditions. We will also enhance the level of convenience in treatments to improve medication compliance, thereby contributing to raising patients’ QOL.

*As of March 2023. As a cream for the treatment of allergic conjunctivitis applied to the periocular area (upper and lower eyelids) (researched by Santen with IQVIA MIDAS 2011-2022. Copyright © 2023 IQVIA., reprinted with permission)

1.        Japanese Society of Ocular Allergology Clinical Guideline Development Committee: Guidelines for the Treatment of Allergic Conjunctival Disease (3rd ed.). Journal of the Japanese Ophthalmological Society 125(8): 741-785, 2021

About Santen
As a specialized company dedicated to eye health, Santen carries out research, development, marketing, and sales of pharmaceuticals, over-the-counter products, and medical devices, and its products now reach patients in over 60 countries and regions. Toward realizing “WORLD VISION” (Happiness with Vision), the world Santen ultimately aspires to achieve, as a “Social Innovator”, Santen aims to reduce the social and economic opportunity loss of people around the world caused by eye diseases and defects by orchestrating and mobilizing key technologies and players around the world. With scientific knowledge and organizational capabilities nurtured over a 130-year history, Santen provides products and services to contribute to the well-being of patients, their loved ones and consequently to society.
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